The Rollei 35 series are the smallest compact full frame 35mm cameras ever produced. The whole range are incredibly well refined and superbly engineered cameras, with very big and clear viewfinders as well as incredibly sharp lenses. 
 
The 35T is one of the later entires to the lineup, entering the market in 1971 and features a 40mm f3.5 Tessar lens of Zeiss design.